The ten-part series, which is set in the 1960s, focuses on the criminals, politicians and entertainers who meet at the first big Miami hotel.
Deadline says that Morgan is in final negotiations for the role of a Jewish-American man who builds the hotel. The show focuses on the character as he makes strange allies and dangerous enemies.
Morgan previously starred as John Winchester in Supernatural and appeared as Denny in Grey's Anatomy. He has also appeared in movies including Watchmen and The Losers.
Production for Magic City is expected to begin in Miami early next year and the show is scheduled to premiere in 2012.